What are the spots on my bell peppers?
I grow King of the North bell peppers each year and for the last several years, some of them have spots. The spots start from the inside of the peppers and eventually are on the outside skin and form dark rotted spots. There is no insect damage that I can see, no holes or cracks in the pepper. About half of our peppers get this. On the same plant we will have perfect peppers and ones with spots. I only notice the spots on the red peppers, but the spots do start out a greenish color, so may be hard to see? The plants are healthy looking with good foliage, and bear lots of peppers. I also grow Jimmy Nardello, Shishitos, and poblanos. None of these have these spots. I do save my seeds from the K of N peppers. Have you any idea what this could be and what I can do about it?
I found several sites from other states that suggest your peppers may be experiencing Stip – a physiological cause.
Stip or colour spotting
This is a physiological disorder resulting in small (1/4” diameter or less), dark spots on the pepper fruit. The exact causes are unknown, but it is usually associated with cool temperatures. Low calcium or excessive nitrogen and potassium may be involved. Varieties differ in susceptibility.
The University of Delaware has some more detailed information here.
So no pesticide spray needed. Just watch the soil nutrients in the late summer.